1. Field of the Invention
This invention relates to both novel and known sulfonyl carbazates as well as their use in the art of manufacturing cellular polymeric materials. In particular, sulfonyl carbazates have been found especially useful as chemical blowing agents in the expansion of polymer. The chemicals of the invention are particularly valuable in the expansion of polymers such as elastomers and plastics which are normally processed at elevated temperatures and especially in plastics which are processed at temperatures above 225.degree. C. Particular chemicals herein are even useful at expansion temperatures in excess of 250.degree. C.
The sulfonyl carbazate compounds of this invention contain at least one chemical group of EQU --SO.sub.2 NHNH--COO--
wherein the oxygen and the sulfur each attach to a various organic group, as hereafter described.